diff --git a/Exercises/.prettierrc b/Exercises/.prettierrc
new file mode 100644
index 0000000..4cb85b8
--- /dev/null
+++ b/Exercises/.prettierrc
@@ -0,0 +1,7 @@
+{
+  "trailingComma": "es5",
+  "tabWidth": 2,
+  "semi": true,
+  "singleQuote": true,
+  "space-before-function-paren": ["error", "never"]
+}
diff --git a/Exercises/1-random.js b/Exercises/1-random.js
index ef5ccaf..15334bb 100644
--- a/Exercises/1-random.js
+++ b/Exercises/1-random.js
@@ -1,9 +1,12 @@
 'use strict';
 
-const random = (min, max) => {
-  // Generate random Number between from min to max
-  // Use Math.random() and Math.floor()
-  // See documentation at MDN
+const random = (min, max = null) => {
+  if (!max) {
+    max = min;
+    min = 0;
+  }
+
+  return Math.floor(Math.random() * (max - min + 1)) + min;
 };
 
 module.exports = { random };
diff --git a/Exercises/2-key.js b/Exercises/2-key.js
index ba7e53a..6ecdde6 100644
--- a/Exercises/2-key.js
+++ b/Exercises/2-key.js
@@ -1,9 +1,14 @@
 'use strict';
 
 const generateKey = (length, possible) => {
-  // Generate string of random characters
-  // Use Math.random() and Math.floor()
-  // See documentation at MDN
+  let result = '';
+
+  for (let i = 0; i < length; i++) {
+    const randomIndex = Math.floor(Math.random() * possible.length);
+    result += possible[randomIndex];
+  }
+
+  return result;
 };
 
 module.exports = { generateKey };
diff --git a/Exercises/3-ip.js b/Exercises/3-ip.js
index 1e2c406..441ea5c 100644
--- a/Exercises/3-ip.js
+++ b/Exercises/3-ip.js
@@ -1,11 +1,11 @@
 'use strict';
 
-const ipToInt = (ip = '127.0.0.1') => {
-  // Parse ip address as string, for example '10.0.0.1'
-  // to ['10', '0', '0', '1'] to [10, 0, 0, 1]
-  // and convert to Number value 167772161 with bitwise shift
-  // (10 << 8 << 8 << 8) + (0 << 8 << 8) + (0 << 8) + 1 === 167772161
-  // Use Array.prototype.reduce of for loop
-};
+const ipToInt = (ip = '127.0.0.1') =>
+  ip
+    .split('.')
+    .reduce(
+      (result, current, index) => result + (+current << ((3 - index) * 8)),
+      0
+    );
 
 module.exports = { ipToInt };
diff --git a/Exercises/4-methods.js b/Exercises/4-methods.js
index c1038e8..a3e80c1 100644
--- a/Exercises/4-methods.js
+++ b/Exercises/4-methods.js
@@ -1,21 +1,40 @@
 'use strict';
 
-const methods = iface => {
-  // Introspect all properties of iface object and
-  // extract function names and number of arguments
-  // For example: {
-  //   m1: x => [x],
-  //   m2: function (x, y) {
-  //     return [x, y];
-  //   },
-  //   m3(x, y, z) {
-  //     return [x, y, z];
-  //   }
-  // will return: [
-  //   ['m1', 1],
-  //   ['m2', 2],
-  //   ['m3', 3]
-  // ]
+const methods = (iface) => {
+  const result = [];
+  for (const method in iface) {
+    if (typeof iface[method] === 'function') {
+      result.push([method, iface[method].length]);
+    }
+  }
+
+  return result;
 };
 
+// console.log(
+//   'methods :>> ',
+//   methods({
+//     m1: (x) => [x],
+//     m2: function (x, y) {
+//       return [x, y];
+//     },
+//     m3(x, y, z) {
+//       return [x, y, z];
+//     },
+//   })
+// );
+
+// function inspectInterface(iface) {
+//   // Get the keys of iface object
+//   let keys = Object.keys(iface);
+
+//   // Filter keys with function type
+//   keys = keys.filter((key) => typeof iface[key] === 'function');
+
+//   // Map the keys array to a desired format
+//   let result = keys.map((key) => [key, iface[key].length]);
+
+//   return result;
+// }
+
 module.exports = { methods };
diff --git a/JavaScript/1-simple.js b/JavaScript/1-simple.js
index b791331..4aa42dc 100644
--- a/JavaScript/1-simple.js
+++ b/JavaScript/1-simple.js
@@ -1,10 +1,10 @@
-'use strict';
+"use strict";
 
 function inc(a) {
   return a + 1;
 }
 
-const sum = function(a, b) {
+const sum = function (a, b) {
   return a + b;
 };
 
@@ -15,7 +15,14 @@ const avg = (a, b) => {
   return s / 2;
 };
 
-console.log('inc(5) = ' + inc(5));
-console.log('sum(1, 3) = ' + sum(1, 3));
-console.log('max(8, 6) = ' + max(8, 6));
-console.log('avg(8, 6) = ' + avg(8, 6));
+console.log("inc(5) = " + inc(5));
+console.log("sum(1, 3) = " + sum(1, 3));
+console.log("max(8, 6) = " + max(8, 6));
+console.log("avg(8, 6) = " + avg(8, 6));
+
+function ipToInt(ip = "127.0.0.1") {
+  return ip
+    .split(".") // превращаем строку в массив, разбивая её на элементы по '.'
+    .map((byte, index) => Number(byte) << ((3 - index) * 8)) // сдвигаем каждый байт на нужное количество битов в соответствии с правилами, указанными выше
+    .reduce((accum, current) => accum + current, 0); // суммируем все, чтобы получить окончательное число
+}
diff --git a/package.json b/package.json
index ebfc0c9..c4de81a 100644
--- a/package.json
+++ b/package.json
@@ -5,7 +5,7 @@
   "author": "Timur Shemsedinov <timur.shemsedinov@gmail.com>",
   "license": "MIT",
   "scripts": {
-    "test": "eslint ./Exercises; hpw",
+    "test": "eslint ./Exercises && hpw",
     "ci": "eslint ./Exercises && hpw"
   },
   "dependencies": {